U.S. Pat. No. 4,103,939, dated Aug. 1, 1978 and entitled "Multi Passage Flexible Connectors", discloses and claims a multi-channel flexible connector for connecting multiple parallel conduits. The input pipes are connected to a housing and the output pipes are connected to a nipple assembly that protrudes from the housing and is free to move angularly with respect thereto, the connector also being provided with a seat and an elastomeric body for accommodating the angular movements. The nipple is provided with a plurality of passages arranged in a circular fashion about the longitudinal axis of the connector. A corresponding plurality of passages is also provided in the elastomeric body, in the seat and in the housing. The inner and outer surfaces of a flared end of the nipple, as well as a plurality of spherical reinforcing rings within the elastomeric body, have their respective surfaces spherical with respect to a center of deflection located on the longitudinal axis of the housing. The elastomeric body is adhered to the opposing spherical surfaces on the nipple and the seat, and it consequently seals the respective passageways from each other and from the external environment at the interface between the nipple and the seat, while permitting the required angular movement. In order to effect a seal at the interface between the seat and the housing that will accommodate a limited longitudinal movement, the portion of the seat in the vicinity of each of the passageways is formed as an individual piston-shaped member and a corresponding cylindrical recess is provided in the housing with the required seal being maintained between each piston and its corresponding cylinder by means of a plurality of O-rings.
U.S. Pat. No. 4,076,284, dated Feb. 28, 1978, and entitled "Ocean Floor Riser Connection" discloses and claims a flexible connector suitable for use to effect a flexible connection in the riser between a deep-sea oil well and an offshore floating platform. As noted in that patent, in such an environment a connector is subject to widely varying forces and may involve subjecting the riser connector to production pressures which could be substantially higher than the hydrostatic head on the outer periphery of the connector. The particular connectors disclosed in that patent have but a single passageway surrounded by an elastomeric sealing member which is maintained under compression by a combination of hydrostatic pressures outside of the unit as well as by the high pressures of the operating fluid within the passageway and by tension forces exerted on the connection, with O-rings being used to effect a fluid-tight joint between a collar located at the upper end of the elastomeric seal relative to an internal cylindrical surface of the housing.
U.S. Pat. No. 3,680,895, dated Aug. 1, 1972 and entitled "Flexible Joint Means", discloses and claims an omnidirectionally flexible joint for fluid conduits subject to high pressures and axial loads, including one embodiment having two inner housings that are capable of separate and independent flexing movements with respect to a common outer housing, whereby a given joint deflection can be accomplished by means of simultaneous deflection of both inner housings so that the load on each respective seal assembly may be cut to half of that which would otherwise have been required with the attendant advantages of lower operating stress on each of the seal assemblies and a longer service life.
U.S. Pat. No. 3,194,589, "Vibration Isolating Pipe Coupling" discloses a coupling member for connecting pipes or tubes and also acts as a vibration isolating element between the sections of pipe being joined. Generally, the coupling member disclosed in U.S. Pat. No. 3,194,589 comprises: (1) a longitudinally-extending housing which forms a tubular conduit; (2) an annular piston-like member which is slidably received by the housing so that its tubular inner surface coacts with the housing to provide a fluid passageway; and (3) a member of axially-compliant seals located between the housing and the slidable piston member for effecting a fluid tight seal between the elements of the coupling and for permitting vibration-decoupling motion between the housing and piston member.
U.S. Pat. No. 3,734,546, "Flexible Pipe Connection" discloses a flexible pipe connection which prevents or minimizes the transmission of sounds produced in the pipeline. The connector disclosed comprises an annular housing with a central cavity and a nipple partially submerged in the cavity. The submerged portion of the nipple has a flared end which serves as the base for two annular elastomeric seals which are placed between the nipple and the housing. The first of these assemblies is located on the interior surface of the flared end and bridges the nipple and the housing to provide a constant inside diameter for the joint so that this diameter corresponds to the inside diameter of the pipes being joined and a smooth, quiet flow of fluid through the joint is assured. The second and larger sealing assembly is placed on the exterior surface of flared end of the nipple and is configured to close the central cavity of the housing and to clear the nipple and housing for flexural movement. The first and second assemblies are in the form of spherical segments and have a common center of rotation in the longitudinal axis of the joint which permits omnidirectional flexure of the joint. The use of rubber O-rings in the inner and outer rings of the first seal adjacent the housing and nipple member and between the collar of the second seal and the flared end of the nipple is also disclosed.
U.S. Pat. No. 4,198,078, "Pressurized Vibrator Isolator" discloses a sound and vibration isolator for use in automotive air conditioning conduit systems wherein vibrations are absorbed within an elastomer. Generally, a cylinder casing communicates with a tubular conduit connection portion coaxial with the cylinder. The cylinder includes an inner pressure face wall perpendicularly disposed to the cylinder axis. A piston member having an elongated tubular form with a head at one end formed by a radially disposed annular flange positioned in axially spaced opposed relationship to the cylinder pressure face wall and a conduit connection stem portion at the other end. The open end of the cylinder is closed by an annular reaction will transversely disposed to the cylinder axis and an elastomer seal and vibration damper is interposed between the piston head and the cylinder reaction wall, and is bonded thereto. Radial clearance exists between the inner dimension of the elastomer and the cylindrical stem of the piston because the elastomer is only bonded to the piston adjacent the head. This construction allows relative torsional deflection between the cylinder and the piston about the axis of the respective connection conduits. Also, limited angular deflection between the piston and cylinder relative to the isolator axis is permitted by the elastomer.
U.S. Pat. No. 3,853,337, "Flexible Elbow Joint for Pipes" discloses a flexible pipe elbow joint with dual end flexure units providing omnidirectional flexural movement and lateral movement of the pipes joined. The joint comprises a 90.degree. elbow with dual end flexure units attached. The flexure units are identical and have bell shaped annular housings with end flanges at the bell mouth. A nipple with a flared end protrudes into the housing cavity and the nipple end is connected to the interior of the end flange by a first scale assembly and to the housing top by a second seal assembly. The first seal assembly closes the bell mouth and the second seal assembly provides for a constant diameter opening through the joint. Both seal assemblies have elastomeric elements which permit omnidirectional flexibility and also lateral movement of the nipple with respect to the housing.
U.S. Pat. No. 3,957,291, "Ball Joint Assembly with Internal Passages" discloses a multi-passage ball joint assembly for connecting a riser or similar pipe to a well pipe primarily in underwater installations. The ball member of the joint assembly has a main longitudinal bore or passage through which well operations may be conducted and at least one passage for conducting fluid. The housing of the joint assembly includes passageways which connect the bore and passages which extend through the ball in all positions of the ball relative to the housing so that fluid can be conducted downward through the ball to activate devices below the joint for other purposes.
U.S. Pat. No. 3,190,374, "Soil Drilling Apparatus Having Means to Change the Direction of the Drill" which comprises a hollow bushing formed in two pivotally connected sections and operable by the pressure of drilling fluid on a part thereof to control the inclination of the motor. The upper section of the bushing is connected to the drill string of the apparatus and is constructed to provide the axis of articulation for the lower section. The upper section also carries a piston having an extension or pushing member that is arranged on movement of the piston to cause the lower section of the bushing which is connected to a turbine to assume an inclined position with relation to the upper section. The driving force exerted by the push member on the lower section is the result of a difference of opposing pressures applied to upper and lower faces of the piston.
U.S. Pat. No. 908,414, "Flexible Ball Joint" discloses a flexible ball joint in conjunction with a ball case which has multiple passages through the ball and the neck corresponding to passages in the case and independent packings for pipes connected to the case.
However, offshore oil drilling and producing operations such as pumping stations, storage and tanker loading facilities, require the use of flexible connectors that can withstand the rigors of a hostile submarine environment in addition to withstanding the tensile and flexural stresses to which the pipes in such facilities are subjected.